Since 1966 it has been evident that fast neutrons are superior to x- or gamma rays for the treatment of cancer in certain organs. It may also be true that neutrons are superior for any kind of cancer. Since 1967, the University of Pennsylvania has been engaged in a project to produce a compact, relatively inexpensive and simple neutron source that would be suitable for fast neutron therapy. This work has been done under contract with The Cyclotron Corporation of Berkeley, California and as of March 1975, the prototype machine had reached and in fact, exceeded the required minimum performance. Since November 25, 1975 The Cyclotron Corporation and the University of Pennsylvania have been designing a new D-T neutron generator which will be a clinically useful configuration. The machine is now fully designed and is being assembled in Berkeley. The contract with The Cyclotron Corporation calls for delivery within eighteen months. However, the contract was delayed five months from June 30, 1975 to November 25, 1975 because of uncertainties concerning the degree of sophistication we should try for in the first clinical machine. This was worked out by the end of November and a contract was issued on November 25, 1975. However, this represented a five-month delay because we could not spend grant money for equipment and other items when we were not sure that we were going to be able to agree on a contract for the machine. Dr. Peter Bloch, who is Co-Investigator and is a physicist, visited the plant in Berkeley and was quite pleased with the design as far as it goes up to now. I have myself made two visits out there and they are obviously doing a very good job and should have the machine ready within twelve months. BIBLIOGRAPHIC REFERENCES: Bloch, P.H., Hendry, G.O., Hilton, J.L., Quam, W.M., Reinhard, D.K., and Wilson, C., "Beam Profiles Measured on a Neutron Generator Having an Effective Target Area 5.5 x 5.5 cm", to be published in Physics in Medicine and Biology, Vol. 20, 1976.